A173061 Arises in classification of base sequences.

1, 1, 1, 1, 3, 4, 5, 17, 27, 44, 98, 84, 175, 475, 331, 491, 1721, 2241, 1731, 4552, 3442, 3677, 15886, 6139, 10878, 19516, 10626, 22895, 31070, 18831, 19640

Offset

0,5

Comments

Column 2 of Djokovic, p.3, Table 1: Number of equivalence classes of BS(n + 1, n). From the abstract of the paper: "Base sequences BS(n+1,n) are quadruples of {1,-1}-sequences (A;B;C;D), with A and B of length n+1 and C and D of length n, such that the sum of their nonperiodic autocorrelation functions is a delta-function. The base sequence conjecture, asserting that BS(n+1,n) exist for all n, is stronger than the famous Hadamard matrix conjecture. We introduce a new definition of equivalence for base sequences BS(n+1,n) and construct a canonical form. By using this canonical form, we have enumerated the equivalence classes of BS(n+1,n) for n <= 30. Due to excessive size of the equivalence classes, the tables in the paper cover only the cases n <= 12."

Links

Table of n, a(n) for n=0..30.

Dragomir Z. Djokovic, Classification of base sequences BS(n+1,n), arXiv:1002.1414 [math.CO], 2010.

Dragomir Z. Djokovic, Classification of base sequences BS(n+1,n), International Journal of Combinatorics, Vol. 2010, Article ID 851857, 21 pages, 2010.

Dragomir Z. Djokovic, Erratum to "Classification of base sequences BS(n+1,n)", International Journal of Combinatorics, Vol. 2010, Article ID 842636, 2 pages, 2010.

Crossrefs

Sequence in context: A290014 A298225 A278919 * A174326 A224890 A263810

Adjacent sequences: A173058 A173059 A173060 * A173062 A173063 A173064

Keyword

nonn,more

Author

Jonathan Vos Post, Feb 09 2010

Status

approved